There are theoretical and experimental evidences for the pseudo-gap in electron doped cuprates being due to interaction between electrons and anti-ferromagnetism(AFM). A remaining issue is on how AFM correlates with pseudo-gap, and eventually with superconductivity. To elucidate the issue, we have performed temperature dependent angle-resolved photoemission studies of an e-doped cuprate superconductor $Sm_{2-x}Ce_xCuO_4$(SCCO) x=0.18 at 20K and 150K. In the case of $Nd_{2-x}Ce_xCuO_4$, the most well known e-doped cuprate, pseudo-gap disappears at around 100 K for x=0.17. Our experimental result reveals that the pseudo-gap of SCCO exists even at 150K for x=0.18. This result implies that the AFM of SCCO survives even in x=0.18, which agrees with previously reported phase diagram of SCCO. Yet, the superconductivity disappears around x=0.18 for both NCCO and SCCO in spite of the difference in the magnetic order. This result sheds a light on the disappearance of superconductivity on the over-doped side.